Convert spline to polyline

[Hải_Duy]

Because we want the boundary line to be a close polyline, we must convert the elipse and spline into a polyline.

One problem I have is that when converting, the more points the weight is, the less points the accuracy is not high.

Please suggest me a simple algorithm so that the connecting segments are minimal

 

new block.dwg

[mhupp]

Maybe run overkill ?

 

Quote

: OVERKILL
0 duplicate(s) deleted
4055 overlapping entities or segment(s) deleted

 

still not enough you are going to have to redraw the radius. that is where most of the points are.

[Hải_Duy]

@mhupp Sorry, can you take a look at this drawing again?

abc.dwg

[Steven P]

pedit?  then select the spline, though this converts the arcs to short lines of the length you specify. You can choose a short length

 

and then http://www.theswamp.org/index.php?topic=19865.msg244892#msg244892 might do it, , I guess 'A' which is the last offering on that page.

 

Will reduce straight edges in the polyline to a single vertex but the curves will still be short line segments

 

 

 

Wish I hadn't seen this because I think there it is possible to make a much better LISP to include arcs instead of straight lines in resulting polyline

[BIGAL]

Did the shape come from a manufacturer that way as a dwg ? Its almost done that way to make it harder to edit. Almost want to trace over with straights and then fillet joining 2 straights.

 

How many shapes involved ? 

 

 

 

[exceed]

(defun c:spl2pl ( / ss i ent ss3 ss2 obj cpcount j )
  (princ "\n Select spline to convert to pline : ")
  (setq ss (ssget '((0 . "SPLINE"))))
  (setq i 0)
  (setq ss3 (ssadd))
  (repeat (sslength ss)
    (setq ent (ssname ss i))
    (command "_explode" ent "")
    (setq ss2 (ssget "_P"))
    (setq j 0)
    (repeat (sslength ss2)
      (setq ent2 (ssname ss2 j))
      (setq obj (vlax-ename->vla-object ent2))
      (setq cpcount (vlax-get-property obj 'Numberofcontrolpoints))
      (command "_SPLINEDIT" ent2 "_P" cpcount "")
      (ssadd (entlast) ss3)
      (setq j (+ j 1))
    )
    (setq i (+ i 1))
  )
  (if (> (sslength ss3) 1) 
    (progn 
      (command "_pedit" "_M" ss3 "" "J" "0" "")
    )
    (progn 
      (command "_pedit" ss3 "")
    )
  )
  (princ)
)

 

1. Roughly, i think this is not you want

 

2. use wmf

 zoom > object 

 wmfout

 wmfin 

 explode it 

 you get 2dpolyline automatically, > scale it and convert 

 

3. save as drawing or wblock spline to oldest .dxf version as you can, ex) R12

and then reopen it.

it changed to 3dpolyline

explode it and then mpedit join them all

Edited November 14, 2023 by exceed

[Hải_Duy]

@BIGALExactly, the supplier gave me the dwg and I want to connect it into a polyline with a minimum number of connection points.

[Hải_Duy]

@exceed This is exactly the code I needed, thank you very much bro